Combining Adaptive and Deterministic Routing: Evaluation of a Hybrid Router

  • Dianne R. Kumar
  • Walid A. Najjar
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1602)


A novel routing scheme is proposed for virtual cut-through switching that attempts to combine the low routing delay of deterministic routing with the flexibility and low queuing delays of adaptive routing on k-ary n-cube networks. In this hybrid routing scheme a message is routed as soon as possible along a minimal path to its destination even though the routing choice may not be optimal. Results show that the disadvantages of making a non-optimal routing decision are offset by its speed. Two pipelined implementations of this hybrid routing mechanism are evaluated and compared to traditional deterministic and adaptive implementations. The experimental evaluations show that both hybrid implementations do indeed achieve their objectives under various types of traffic patterns.


Virtual Channel Message Size Message Length Physical Channel Adaptive Channel 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Dianne R. Kumar
    • 1
  • Walid A. Najjar
    • 1
  1. 1.Department of Computer ScienceColorado State UniversityFt. CollinsUSA

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